Unique Dining Experience for 20 people?

It's that time of year! I've been put in charge of finding the restaurant for our office holiday dinner, and I'm looking for something a little bit "unique" for a group of about 20 of us. So far on my list are places like Yer Ma's Kitchen at Dora Keogh (family style dining in a private home-style kitchen), The Corner House Restaurant (not quite as unique, but I've been told the atmosphere is cozy and private), and The Red Violin (Brazilian BBQ)....

I'm looking for something that is either a really unique/quirky experience because of atmosphere or dining experience. Most cuisines are fine, but nothing *really* out there as we do have one kinda-picky eater (so no authentic homestyle cantonese with unidentifiable animal parts).

Any suggestions? We're looking to book for December 22nd, which is a Thursday, and accepting credit cards would be appreciated :D

We dined at Corner House last week and had a very good meal. The special was elk with spaetzle and it was done to perfection, and a bargain at $29.You could probaly have a private room as there are several small rooms, one of which would be quite suitable.